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Optics Communications
journal homepage: www.elsevier.com/locate/optcom
Experimental demonstration of an NOMA-PON with single carrier
transmission
Bangjiang Lin
a,
⁎
, Zabih Ghassemlooy
b
, Xuan Tang
a
, Yiwei Li
a
, Min Zhang
a
a
Quanzhou Institute of Equipment Manufacturing, Haixi Institutes, Chinese Academy of Sciences, Quanzhou, China
b
Optical Communications Research Group, Faculty of Engineering and Environment, Northumbria University, Newcastle, UK
ARTICLE INFO
Keywords:
Passive optical network (PON)
Non-orthogonal multiple access (NOMA)
Single carrier transmission
ABSTRACT
We introduce a non-orthogonal multiple access (NOMA) scheme for next generation passive optical network
(PON) with single carrier transmission and frequency domain successive interference cancellation (FD-SIC),
which offers low peak to average power ratio, a good balance between throughput and fairness, and a higher
system capacity for a larger number of users. The feasibility of the proposed scheme is verified with 6.6 Gbps
bidirectional NOMA-PON transmission. The effect of power allocation on the bit error rate performance is
investigated.
1. Introduction
Passive optical network (PON) is the best solution for broadband
access, due to its low cost and large capacity [1–3]. As bandwidth-
hungry video applications continue to fuel the rise in bandwidth
demand, the next generation PON should be upgraded to support
higher data rate and more users. Currently most deployed PONs are
gigabit PON (GPON) and Ethernet PON (EPON), both of which employ
time-division-multiplexing (TDM) to achieve cost effectiveness.
However, it suffers from high transmission impairment because of
chromatic dispersion when the data rate is beyond 10 Gb/s. Many PON
technologies have been proposed to provide beyond 10 Gb/s transmis-
sion. There are time- and wavelength-division multiplexing (TWDM)-
PON which stacks multiple 10 Gigabit PON using wavelength division
multiplexing (WDM) [4,5], WDM-PON which provides a virtual point-
to-point fiber access connection via a dedicated wavelength to each
optical network unit (ONU) [6,7], orthogonal frequency division
multiple access (OFDMA)-PON which provides high spectrum effi-
ciency by employing a large number of orthogonal subcarriers over-
lapping in spectrum [8,9], and code division multiple access (CDMA)-
PON which uses codes to separate users over the channel [10]. In these
PON schemes, different ONUs are allocated to orthogonal resources in
either the time, frequency (wavelength), or code domain in order to
avoid or alleviate interference.
Recently, non-orthogonal multiple access (NOMA) as a new multi-
ple access technology has attracted much research attention, as it offers
a better balance between system fairness and throughput [11–13]. The
NOMA scheme is also applied for visible light communications to
enhance the achievable throughput [14,15]. Unlike the orthogonal
multiple access (OMA) techniques such as time division multiple access
(TDMA) and OFDMA, NOMA allows multiple users to simultaneously
transmit their signals via the same frequency band, resulting in signal
overlapping in both time and frequency domains, as well as signal
multiplexing in the power domain. The successive interference cancel-
lation (SIC) is used at the receiver (RX) to separate the users. As a
result, significant enhancement in the sum rate and throughput can be
achieved.
In this paper, we propose a NOMA scheme with single carrier
transmission and frequency domain successive interference cancella-
tion (FD-SIC) for PON which offers a high throughput and spectral
efficiency. Bidirectional NOMA PON transmission with two optical
network units (ONUs) is experimentally demonstrated to verify the
feasibility of the proposed scheme. The experiment results indicate that
the optimum power allocation ratio (PAR) for the downstream and
power difference between the two ONUs for the upstream are about
0.25 and 7 dB, respectively. We also compare the FD-SIC with joint
detection (JD) method proposed in [16]. Since the JD is maximum-
likelihood (ML) optimal, it offers better bit error rate (BER) perfor-
mance than FD-SIC.
2. Technique principle of NOMA based on FD-SIC
Fig. 1 shows the schematic diagram of proposed NOMA-PON with
N ONUs. In the downstream, the source data for each ONU is mapped
and grouped into blocks prior to power allocation, respectively. Cyclic
prefix (CP) is added in the front of each block to combat the chromatic
http://dx.doi.org/10.1016/j.optcom.2017.03.039
Received 21 February 2017; Received in revised form 16 March 2017; Accepted 16 March 2017
⁎
Corresponding author.
E-mail address: linbangjiang@163.com (B. Lin).
Optics Communications 396 (2017) 66–70
0030-4018/ © 2017 Elsevier B.V. All rights reserved.
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